Winding and reeling means for sound recording and reproducing apparatus



Dec. 15,1942- L. A. .HERZIG 1 2,304,913 WINDING AND REELING MEANS FORSOUND RECORDING AND REPRODUCING APPARATUS Filed April 30, 1940 9Sheets-Sheet 1 7 121 11 mman s.

' mlllllllilllllmn in D 1 1941 L. A; HERZIG 2,304,913

WINDING AND REELING MEANS FOR SOUND RECORDING AND REPRODUCING APPARATUSFiled April 50, 1940 9 Sheets-Sheet 2 &

I me A90 /0' a? #7 INVENTOR Q Q a m Q ATTORNEYS Dec. 15, 1942.

- A. HERZIG 2,304,913 WINDING AND REELING MEANS FOR SOUND RECORDING AND.REPRODUCING APPARATUS Filed Ap ril so, 1940- 9 Sheets-Sheet s INVZNTOR vafflfmw ATTORNEYS 9 Sheets-Shelet 4 ltlllll L. A. HE RZI G Filed April:50, '1940 Dec. 15, 1942.

WINDING: AND REELING MEANS FOR SOUND RECORDING AND REPRODUCING A IPARATUS Dec. 15, 1942. L. A. HERZlG I WINDING AND REELING MEANS FORSOUND RECORDING AND REPRODUCING APPARATUS 9 Sheets-Sheet 5 Filed April30, 1940 INVENTOR. 5%

' ATTORNEYS.

M W a Dec. 15, 1942.

L. A. HERZIG WINDING AND REELING HEARS FOR SOUND RECORDING ANDREPRODUCING APPARATUS Filed April 30. 1940 9 Sheets-Sheet 6 De. 15 1942AIHERZIG 2,304,913

WINDING AND REELING MEANS FOR souND RECORDING AND REPRODUCING APPARATUSFiled April 30, 1940 9 Sheets-Sheet 7 i W U INVENTOR ATTORNEYS Dec. 15,1942.

L. A. HERZIG I WINDING AND FEELING MEANS FOR SOUND RECORDING ANDREPRODUCING APPARATUS 9 Sheets-Sheet 8 Filed Ap ri], so, 1940 ATTORNEYSDec. 15, 1942. v :L. A. HEfizle 7 2,304,913 WINDING AND REELING MEANSFOR SO UND RECORDING AND REPRODUCING APPARATUS Filed April 30, 1940 9sheets-sheet 9 DIIIQZ/EI/UEIEIEID'D out; @unm s l I I I 1 l l I I 6mcfhncxunum' CIUUEIUEIEJEID a INVQE'NTOR Q a Emu ATTORNEYS Patented Dec.15, 1942 2,304,913 WINDING AND REELING DIEANS FOR SOUND RECORDING RATUSAND REPRODUCING APPA- Lconard A. Herzig, Jackson Heights, N. Y., as-

signor to Lon-Ga-Ton e, Inc., New York, N. Y.,

a corporation of New York Original application April 24, 1937, SerialNo.

138,751. Divided and this 1940, Serial No. 332,442

5 Claims.

This invention relates to a photographic sound recording and reproducingsystem and is a division of my copending application Serial No. 138,751,filed April 24, 1937, now Patent #2315,- 468, issued September 24, 1940.

The principal object of the invention is to provide a new and improvedapparatus for continuously and uninterruptedly recording on or"reproducing from a plurality of parallel sound tracks or forplaying anyselected part or track of the completed record.

A related object of the invention is to provide apparatus of the abovetype, including a novel friction take-up mechanism for driving the filmreels, means to maintain,a predetermined tension on the film and to takethe shock from the application April 30,

#2,215,468, a sensitiveand accurate control of the reversing mechanismis obtained by changing the grid potential of a space discharge tube bythe capacity effect of a conducting bar or strip which is formed in orattached to the film adjacent the ends of the sound tracks, the controlbeing effected when the conducting strip reaches a predetermined pointwith respect to the sound gate'.

An important feature of the present invention resides in the provisionof an improved film an improved film winding and reeling means for filmwhen the drive is reversed, means to adjust the friction of the take-upmechanism so as to supply a force proportional to the weight of the filmbeing driven, and means for controlling such adjustment in accordancewith the length of film employed at any given time.

The invention is particularly applicable to apparatus for recording orreproducing sound forv broadcasting purposes, for assemblies, for recordlibraries or for other purposes for which phonographs or film haveheretofore been used. An

.important feature of the recording and reproducing system disclosed andclaimed in my abovementioned Patent #2215368, with which the winding andreeling apparatus of the present invention is adapted to be used,resides in the use of a comparatively short film containing a. pluralityof sound tracks which are played successively. A standard width 35 mm.film may, for example, have some thirty diflerent sound tracks which arejoined by loops so arranged that the scanning light follows the loops onthe changeover without audible variation. The film is held on two reels,as hereinafter described, and is fed first -in one direction and then inthe other for scanning each of the different connected tracks whichconstitute the sound record.

In the preferred embodiment of my sound recording and reproducing systemthe film isfed past a sound gate by a pair of sprockets which arereversibly driven in unison. A pair of driveshafts preferably havingsuitable vibration dampeners are continuously driven in oppositedirections and an electrically operated clutch mechanism is provided toselectively connect the sprockets in driving relationship to therespective driveshafts. This mechanism is automatically operated by thefilm itself whenever theend of a sound track has been reached, or it maybe operated manually. In the preferred embodiment, disclosed and claimedin said Patent winding and reeling means for sound recording andreproducing apparatus of the above type. The winding and reelingapparatus includes an adjustable friction drive for the take-upmechanism' which may be adjusted in accordance with the length of thefilm so that more power is supplied to operate the heavier reels whenlong films are used. This adjustment is controlled by a dial which maybe suitably graduated to read in feet of film. The apparatus alsoincludes spring-pressed guide rollers which maintain a predeterminedtension on the film and absorb the shock on the film and thereby preventtearing during reversal. Means are also provided in conjunction with thewinding and reeling apparatus to compensate for variations in length ofthe film due to temperature changes, etc., such means being arranged topermit necessary adjustments without changing the arc of contact of thefilm with the film gate.

These and other'features and advantages of the invention will bedescribed in connection with the accompanying drawings, in which:

Fig. 1 is a top plan view of my preferred apparatus as adapted forrecording purposes;

Fig. 2 is a vertical section taken on line 22 of Fig. 1; v

Fig. 3 is a transverse section taken on line 3-3 of Fig. 1, showing thedriving, reversing and rewinding mechanisms;

. Fig. 4 is a detail section on line 4-4 of Fig. 3, showing themechanical filter;

Fig. 5 is .a horizontal section through the apparatus, taken on line 55of Fig. 3;

Fig- 6 is an enlarged longitudinal section ofi the recording unit shownin Fig. 1;

Fig. 7 is an electrical diagram of the recording unit shown in Fig. 6;'

Fig. 8 is a view similar to Fig. 6, but showing the reproducing unitadapted to be used interreproducing of Fig. 2, showing details of themechanism for controlling the position of the aperture plate:

Fig. 12 is another sectional view of said control mechanism, taken online l2-l2 of Fig. 2; Fig. 13 is a horizontal section taken on line13-43 of Fig. 3, illustrating the sound gate and the threading andadjusting mechanism for the Fig. 14' is a vertical section on line l4i4of r Fig. 5, showing the rewind mechanism;

Fig. 15 is a detail section on line Iii-l of Fig. 13, illustrating theparallel adjustment of the film guiding rollers;

Fig. 16 is a vertical section on line IB-id of referring to variousdetails of construction, but' it will be understood that these terms areto be given as broad an interpretation as the state of the art willpermit.

The machine shown in the drawings comprises a top plate i (Figs. 1 to 3)on which are mounted a pair of reels 2 carrying the film 3 whichcontains the sound record. This film may be of the usual type employedin motion pictures and is shown more in detail in Fig. 18 as having a.plurality ofparallel sound record tracks 4 which extend oversubstantially the entire length of the film and are ioined at their endsby loops ii. The successive tracks are recorded with the film moving inopposite directions so that a continuous sound record is obtained byfollowing the'tracks in succession and reversing the film as the end ofeach track is reached. The film has the usual perforations 8 whichcooperate with suitable teeth on the drive sprockets and is providedadjacent its two ends, at predetermined points with respect to the loops5, with strips I of conducting material which may be sprayed or painted.on the film or may be formed separately and attached thereto in anyconvenient way.

The conducting strips] are used for automatically reversing the film 3in a manner hereinafter described. It is to be understood that thefilmitself may be of any suitable or standard construction. The soundtracks 4, however are all of exactly the same length and the loops 5 arealigned in the same transverse section of the film so that the scanningray can be caused to exactly follow these loops'on each reversal of thefilm.

This exactness in the position of the various loops is obtained by thecontrol mechanism herein-' after described.

Referring again to Figs. 1 to 3, the film 2 is passed between the reels2 over a pair of drive or feed sprockets iii and over a film Bate ll.

Suitable spring-pressed guide rollers i2 r equivalent means are providedto take up the slack of the film and to absorb the shock ofreversai ashereinafter described. Idler rollers I 8' and i i are provided forsuitably guiding the film with re- 4 spect to thefeed sprockets l0and-the gate II. a v

The film gate ll supports the fllm in a position to be scanned by lightfroma light source I! which is focussed by a telescope or lens system Iontoithe-ilim. film gate Ii. adjustable supports a reel 2. for rotationtherewith idler rollers l3, light source l5, telescope l6 and associatedmechanisms are mounted as a unit on a panel I8 which is adapted to beremoved from Take-up mechanism The take-up mechanism for driving thereels 2 is shown in detail in Figs. 2 and 5 and includes a motor 20which is mounted on suitable brackets 2| supported on the base 22 of themachine. The motor 20, through a reduction gear 23, drives pulleys 24 inopposite directions. These pulleys carry belts 25 which drive thepulleys26. Each pulley 26 is mounted on a sleeve 21 which is rotatablyheld in a bearing 28 supported by a bracket 29 which is attached to thetop plate I of the machine. Each sleeve 27 carries a disk 30 on which afriction disk 3| of suitable friction material is supported as shown inFig. 2. Engaging this friction disk ii is a driven disk 32 which iskeyed, as by key 33, to a shaft 34 which extends through the sleeve 27and is rotatable therein. The shaft 34 extends through a bearing 35which is formed on the bracket 29 and by means of a lever 36 which isadapted to fold over onto the top of the reel for the above purpose.

For varying the amount of friction I provide a pair of pivoted arms 40which are pivoted at 4| to cars 42 carried on the top plate I of themachine. Each arm 40 is provided at one end with a fork 43 carryingadjustable pins 44 which seat in a rotating collar 45. A spring 46 isseated around the shaft 34 between the collar and the driven disk 32 toapply pressure to said disk dependent upon' the amount of compression ofsaid spring. The other ends of the arms 44 are p connected by pins 50 toa collar 5| which is carried on shaft 52 extending through a bushing 53a pulley 24 which in turrr attached to the top plate I of the machine.The

shaft 52 is provided at its end with threads 54 as shown in Fig. 16. Anadjusting knob 55 is attached by screws 58 to a threaded collar 51 whichis in threaded engagement with the shaft 52. The collar 51 is iournaledbetween the bushing 53 and an annular member 58 which is rigidlyattached to the top plate i by screws 59. The arrangement is such thatrotation of the adjusting knoblS causes the shaft 52 to be threadedupwardly or downwardly through the bushing '53 and thereby cause pivotalmovement of the arms 40 for varying the pressure of the springs In theabovedescribed take-up mechanism each lower disk 30 is driven by a belt25 from 'is driven by the motor 24. The lower disk 30 drives the upperdisk 32 by the friction obtained by the pressure of the spring 48. Thedisk 82, being keyed to the shaft 84, drives the shaft and the reel 2which is attached thereto. If desired, an index may be provided bymounting a disk at the end of the shaft 52 within the knob it andvisible through a slot Si in said mob as shown in Fig. 16. The diskaccordingly moves axially and, by its position, indicates the adjustmentof the springs 48.

A suitable scale may be provided on the knob 58 o r with thedisk t! forthe foregoin The reel is locked to shaft 34 while it is being driven bythe feed sprockets I9.

so as to feed the same from one reel to the other.

Drive for feed sprockets Feed sprockets I9 are driven from the motor 29by means of a driveshaft 65 attached to the motor (Figs. 2, 3 and 5) andcarrying a flywheel 66 by which irregularities in the drive are largelyeliminated and hunting of the motor is prevented. The shaft 65 isconnected by a flexible coupling 61 to a helical gear 68 which drives apair of helical gears 69 at the same speed and in opposite directions.The gears 69 'are rotatably mounted on sleeves 19 which are journaled inbearings 1I carried on brackets 12 which are attached to the top plate Iand the base 22 of the machine in a convenient manner. The gears 69 eachcarry a spider 13 having a plurality of arms 14 (as shown in Fig. 4)which are connected by springs 15 to pins 16 which are formed on orattached to flywheels 11. 11 .are attached to the sleeves 19 and areeach attached to a sleeve 18 which is part of the lower tooth element 19of a one-way clutch 89. The upper tooth element 8| of this clutch 89 ispart of sleeve 82 which is journaled in bearings 83 carried by thebracket 12. Each sleeve 82 carries a gear 84 meshing with a gear85-which is attached to the shaft 86 on which the drive sprocket I9 isfixed. The two gears 85 are preferably split gears of any suitable typedesigned to'eliminate backlash or play; and these gears are connected byan idler gear 81 so as to operate in unison and at a uniform speed.

For operating the clutch member 89 there is provided a rod 99 whichextends through each sleeve 19 and is provided with a collar 9| which ispositioned below the upper tooth element 8| of the clutch 89 andisadapted when elevated to raise the upper tooth element suiiiciently todisengage the tooth from the lower element 19. The rods 99 are connectedto a pivoted arm 92 which is pivoted at 93 between the arms of a doublebracket 94 supported on the base 22 as shown in Fig. 3. The bracket 94also provides bearings 95 in'which the' drive shaft 65 is journaled asshown in Fig. 2. I

The ends of the arm 92 are attached to cores .98 of solenoids 99 whichare arranged to control the position of the arm 92. The arrangement issuch that when one of the solenoids 99 is energized the core 98 and therod 99 attached thereto are pulled downwardly, thereby causing thecorresponding clutch 89 to engage while disengaging the opposite clutch.The direction of drive of the sprockets I9 is accordingly dependent uponthe particular solenoid 99 which is energized at any particular time.The motor 29 and the flywheels 11 are rotated continuously. When one ofthe clutches is displaced, however, the corresponding'driveshaft picksup and drives the sprocket I9. The springs 15 provide a loose couplingbetween the respective flywheel 11 and the associated gear 69 so thateach spider forms a mechanical filter or vibration dampener to eliminateminor vibrations or variations in the The flywheels pendent selectionsor programs.

drive from being applied to and effecting the uniform rotation of thefeed sprockets I9. By interconnecting the driveshaft for the two feedsprockets I9 by means of the gear 81 any play or lost motion isprevented and the gears are caused to operate in exact unison. Thereversal may be effected substantially instantaneously when one of thesolenoids is energized. The lock nuts on rods 99 hold these rods inposition and permit vertical adjustment of the upper halves of theassociated clutches 89.-

- In order to maintain the clutch 89 engaged after the rod 99 has beenmoved downwardly by energization of the solenoid 99 and withoutrequiring the solenoid to be continuously energized, a suitable holdingmeans may be provided. -In the embodiment shown, this holding means maycomprise electromagnets I99 which are suitably mounted on the frame ofthe machine and cooperate with armatures I9I carried by the pivoted arm92 as shown in Figs. 3 and 19. The operation of electromagnets I99 willbe described later.

High speed rewind mechanism In certain instances it is desirable torewind the reel at a higher rate of speed, as for example when thevarious film tracks are used for inde- In that event when one selectionhas been completed it may be desired to rewind the film preliminaryto'playing a second selection. This may be accomplished by providing ahigh speed rewind, one form of which is shown in Figs. 3 and 14. In theembodiment shown the rewind comprises a flexible driveshaft I98 which isdriven by a gear I99 meshing with one of the helical gears 69. Theflexible driveshaft I98 is attached in driving relationship to afriction disk II9 which. is adapted to be brought into drivingengagement with a second friction disk II I which is mounted on theshaft 86 of the corresponding feed sprocket I9 which is normally drivenby the gear 69 from which the power is taken. The friction disk H9 ismounted on a housing I I2 which is attached by a block II3 to theflexible driveshaft I98 and is mounted for rotation on a shaft 4 by'means of a collar H5. I

The shaft I I4 is pivoted at I I6 to ears I I1 attached to the top plateI of the machine. The pivotal position of the shaft I I4 is determinedby an arm I29 having a forked end I 2I which is adapted to be clamped bya screw I22 about the arm I I4 and at its other end is attached to a rodI23 which engages the core I24 of a solenoid I25. The arrangement of theabove parts is such that when the solenoid I25 is energized the core I24and the rod I23 are pulled downwardly thereby pivoting the arm I29 andthe shaft, H4 and causing the friction disk II9 to bear against anddrive the friction disk III. When the solenoid I25 is deenergized, thedisk H9 is brought out of'engagement with the disk III by the resilienceof the flexible drive I98 or by any other suitable means not shown.

For holding the arm 92 in neutral position with both clutches 89disengaged, when the machine is to be stopped or when the high speedrewind mechanism is to be used, two springs I39 balance the arm 92 asshown in Fig. 3.

Recording head l6 and the film gate H together with associatedmechanisms hereinafter described. The film gate II comprises a circularhousing I45 mounted in a cup I46 which is attached to the panel I8 bysuitable means such as screws I41. A pair of rotating rings-I48 and I49are mounted on the housing I45. These rings are provided with shouldersI58 and I5I respectively, between which the film 3 is seated. Thehousing I45 is also provided with opposite apertures I52 and I53 whichare aligned with the scanning ray hereinafter described. The apertureI52 permits the focus of the light ray on the film to be properlyadjusted, while aperture I53 permits visual inspection of the focussingoperation. In the form shown the lower ring I48 is mounted for rotationdirectly on the housing I45 and is provided with a lip I58 which isseated between the'shoulder I55 formed in the housing I45 and thesurface of the cup I46. The lip I58 serves to prevent axial motion ofthe ring I48.

The upper ring I89 is shown as insulated from the housing I45 for a.reason to be described. For this purpose the upper ring is attached toan inner rotating ring I88 from which it is separated by a ring I6I ofinsulating material. The

avoid making electrical contact therewith. The

ring I49 is thus insulated by the ring I8I from the housing I45. Formaking an electrical contact with this ring a spring brush I18 isprovided which bears against the surface of the ring I99 and is attachedto the locking ring I88 by means of an insulating bushing I1I. Anelectrical connection may be made to this brush I18 which is fastened tothe ring I84 by screw I12. It will be noted that the film 3 is supportedon the rings I48 and I49 as it passes over the housing I 45 constitutingthe film gate II and is thereby held in proper position to receive thescanning ray.

'The glow lamp MI is preferably formed with elongated electrodes I andI18 as shown'in Fig. 7. These electrodes are made substantially longerthan the area of the film 8which is to be scanned so that light may befocussed over the entire width of the. film, with substantially equalintensity. In the form shown the electrode I15 is channel-shaped andconstitutes the cathode, whereas the electrode I16 is in the form of alooped wire registering with'the edges of the channel-shaped electrodeI15 and constitutes the anode. This elongated construction permits auniform light intensity to be radiated from a substantial portion of theglow lamp. This light is focussed by a suitable lens system carried bythe telescope tube I 8 over the entire width of the film 3. In the formshown the telescope tube I8 carries a pair of cylindrical lenses I18 theaxes of which extend in a direction transverse to lens I19 and arearranged so as to concentrate the rays received from the glow lamp IdIover an area extending the full width of the film 9. This light isconcentrated and focussed in a narrow vertical band by means of thecylindrical lens I19 which is arranged with its axis extending in avertical direction. The arrangement is such that this band whichconstitutes the scanning axially so as to permit proper focussing of thelight rays from the glow lamp III.

In order to confine the ray to one sound track of the film at a time anaperture plate I85 is provided between the glow lamp MI and thetelescope tube I6. This aperture plate is formed with a narrow slit I88corresponding in width to the width of oneof the sound tracks asindicated in Figs. 6 and 12 and is mounted for sliding vertical movementin a shield I81 which is carried by the telescope tube I8. The apertureplate I85 is provided with a downwardly extend- ,ing portion I88carrying rack I89 which meshes with a gear I98. The gear I98 isadjustably fastened to a shaft I9I which extends through the front wallI 92 of panel I8 and carries a :knob I98 by means of which the positionof the aperture plate I85 may be adjusted. It will be noted that thegear I98 is sufficiently long to permit slight axial movement of therack I99 as the aperture plate I85 and telescope tube I8 are adjustedfor focussing the light in the manner described above. v

For shifting the aperture plate I95 between successive film tracks apawl and ratchet mechanism is provided which comprises a ratchet gearI98 (Figs. 6 and 11) carried on the shaft I9I and held between bearingsI99 of said shaft which are carried in bracket Z88 attached to the panelI8. A pawl 2M is pivoted to a split arm 288 which is journaled on theshaft I9I on opposite sides of the ratchet gear I98 as shown in Figs. 5and 11. The pawl 281 rests against an adjustable stop 289 (Fig. 11)which is carried by an arm 285 (Fig. 5) attached to the bracket 288. Thepawl 2% is normally held out of engagement with ratchet gear I98 by aspring 285. A locking pawl 291 is pivoted as at 288 on an arm 289attached to the bracket 288 and is moved toward the ratchet wheel I98 bya spring 218. Adjustable stop 283 is carried by the arm 282 to engagethe locking pawl 281' and hold the same out of contact with the teeth ofthe ratchet wheel I98 when the wheel is not actuated. The am 282 isattached to core ZII. of a solenoid ZIZ which is adapted when energizedto cause the pivotal movement of the arm 282 for stepping the ratchetwheel I98 around one tooth. Suitable means, such as a spring 2I9, may beprovided for returning the arm 282 to the position shown in Fig. 11 whenthe solenoid is deenergized.

For holding the ratchet wheel I98 in a given position a disk'2l5 (Figs.6 and 11) is mounted I gage-the disk 2i 5 between the teeth 2I5 so as tosecure the ratchet mechanism in any adjusted position. It is to be notedthat when the solenoid 2I2 is deenergized the arm'282 is in the positionshown in Fig. 11 and the pawls ml and 281 are held out of engagementwith the ratchet wheel I98 by the stops 289 and 203, respectively. The

shaft I9I may then be rotated by means of knob I98. This knob ispreferably provided with graduations 228' which register with a suitableindex on the front I92 of panel [8 to indicate the position of theaperture I86. This index may. for example, be numbered to indicate thenumber of the sound track which is in position to be played or recorded.This hand adjustment may be used, for example, when it is desired tosetthe machine to record on a given sound track. The dial likewise turnswith the shaft I91 during the automatic operation of the machine andthereby indicates the position of the scanning ray at any particulartime. v

It is to be understood that the entire ratchet mechanism including thesolenoid 2| 2 may be re movable as a unit with the panel 18. Suitable vquick detachable plugs, not shown, may be provided for breakingtheelectrical circuit when the recording head is thus removed.

As shown in Fig. 6, a shield 225 having an aperture 226 in alignmentwith the telescope tube l6 may be positioned over the glow lamp Hi to aprevent light rays from going any place except through the apertures 226and 234, the latter of which is used for monitoring purposes as shown inFig. 1 and as described below. This shield may have suitable springclips 221 by which it is securely seated over the glow lamp. The glowlampmay be provided with a suitable vibration dampening socket 228 bywhich it is connected to a supply circuit in the usual manner.

The glow lamp is actuated as indicated in Fig. 7 by the output circuitof an amplifier 230 which is fed in the usual manner by a microphone 23l or by any other suitable pickup means. In order to assist inlisteningin, a photoelectric cell 233 is mounted on the panel .18 asindicated in Fig. 1

in a position to be energized directly by the glow lamp 14!. The shield225 is provided with a slit 234 opposite the photoelectric cell 233 asshown in Fig. 1 so as to permit rays from the glow lamp to passtherethrough. The photoelectric cell 233 is preferably made withelongated elements 235 which extend in an axial direction substantiallycoextensible with the elongated elements I15 and I16 of the glow lamp I4|. This photoelectric cell 233 may be connected with the input circuitof astandard amplifier 236 the output circuit of which may be connectedto a suitable reproducing device 231, such as aloud speaker, earphonesor the like. It will be evident that the photoelectric cell could bemounted in other positions; for exmple, it could be mounted in back ofor within the film gate II in which case it would receive only thescanning ray which has passed through the film.

It is to be understood that the optical system within the telescope tubel6 maybe varied as desired. In general the optical system should bedesigned to focus the light in the form of a fine vertical band equal tothe entire width of the film so that the aperture plate in movingvertically can cut off all of the light except that corresponding to theselected sound track. In this way it is only necessary to move theaperture plate in shifting from one sound track to another. Theremainder of the mechanism remains stationary. In the embodiment shownan upward movement of the aperture plate will cause a downward movementof the scanning rayat the film and vice versa. The lens system, however,could be arranged to produce parallel rays in which case the movement-ofthe aperture would correspond to the movement of the scanning ray at thefilm.

In the above-described mechanism the scanning rays may be shifted fromone sound track to the next with great rapidity inasmuch as it is onlynecessary to move the comparatively. light weight aperture plate. Themovement can also be accurately controlled by the automatic timingmechanism, hereinafter described, so as to synchronize exactly with thereversal of the film at the end of each sound track. v

Reproducing. head The machine is so constructed that the reproducinghead shown in Fig. 8 is interchangeable with therecording head shown inFig. 6. The reproducing head comprises a panel 245 which is adapted toseat on and be secured to thetop plate of the machine in place of thepanel It as shown in Fig. 1. This panel 245 carries a cup 246 which isattached thereto by suitable screws 241 and supports a housing 248 whichforms the film ,gate. The housing 248 is provided with a cylindricalbore 249 in which the photo-electric cell 250 is adapted to bepositioned. It is also provided with an opening 25I which extends oversubstantially the entire width of the film so that Y the rays from thevarious soundtracks can pass to the photoelectric cell. The film issupported upon a pair of rotating rings 252 and 253 which are similar inconstruction to the rings M8 and I49 described above in connection withFig. 6.

260' which is engaged by the flange 26l formed on a locking ring 262.The spring 263 is employed to keep the film guide flange 255 in constantcontact with the upper edge of the film 3 during operation even thoughwear should take place. Th fiange 2'61 terminates short of the ring 253so that this ring is electrically insulated from the housing. Contact ismade to the ring 253 by means of a flexible brush 264 which is attachedto an extension 265 of the housing and is insulated therefrom by bushing266. The extension 265 carries a cap 261 which closes the top of thehousing and forms a socket for making the electrical connection to thephotoelectric cell 250. The socket may be of any convenient or standardconstruction for this purpose. Suitable spacing elements 266 of softmaterial such as rubber may be provided at the bottom of the housing 248and within the central bore 249 so as to support the photoelectric cell250 and to prevent vibration from being imparted thereto.

The housing 248 is also provided with a vertical bore 210 in which anaperture plate 211 slides. The aperture plate is provided with anaperture 212 of a suitable dimension to pass light only from one soundtrack of the film at a time. The photoelectric cell is formed with apair of elongated electrodes 213 and 214, as indicated in Fig. 10, sothat the effect of the scanning ray on the film is unchanged as the raymoves across the film.

The aperture plate 21l carries on its lower end a rack 216 which engagesthe gear 211 held on the shaft Hi. to shaft 19! shown in Fig. 6 andcarries similar ratchet mechanism which has been given conespendingreference numerals with primes aflixed The shaft I91 corresponds cell.

plate could be placed in some other position if.

thereto, and the description of these parts will accordingly not berepeated. It is to be understood'that the entire ratchet mechanism ofFig. 11, including the arm 202, the solenoid 2|2 and associated parts isduplicated in the reproducing head of Fig. 8 and this reproducing headis removable as a unit to replace the corresponding mechanism in therecording head.

The reproducing head is also provided with a socket 280 in whichexciting lamp 28! is held. This exciting lamp is provided with anelongated filament 202 as shown in Fig. 10, which is of such length thatrays of equal intensity are propagated over the entire apertured area ofthe telescope tube to be described. This filament 282 may be held inposition by a spring 283 which is adapted to maintain the filament tightunder all conditions. This is important inasmuch as the image of thefilament is to be focussed onto the film and any variations thereofwould cause corresponding distortion in the reproduction.

The reproducing headis provided with a telescope tube it which issimilar in construction to the telescope tube i6 of Fig. 6 and carries asuitable lens system. The elements of the tube and the lens haveaccordingly been given the same reference characters with primes afiixedthereto and a description thereof will not be I repeated.

The-lenses in general are adapted to focus an image of the elongatedfilament 282 on the film 3 as the film passes the opening l in thehousing 243. The image must be of equal'intensity across the entirewidth of the film inasmuch as it is to cooperate with the various soundtracks thereon. The aperture'plate 2H cuts -oii all of the rays passingthrough the film except the rays through the selected sound track whichare permitted to pass through, the aperture 212 and to be impressed uponthe photoelectric cell 250. As the aperture plate is stepped upwardly ordownwardly by means of the ratchet mechanism the scanning ray is thusshifted from one sound track to the next in a manner similar to thatdescribed in connection with the aperture plate 35 of Fig. 6. In thereproducing head, however,

the scanning rays are continuously applied to the entire film width andthe aperture plate is positioned between the film and the photoelectricIt is to be understood that the aperture desired. For example, theaperture plate could be located between the exciting lamp 28$! and thetelescope tube 'as shown in Fig. 6, or it could be located between thetelescope tube and the film 3. 7

Guide rollers ing the shock on the film during reversal. Each of theseguide rollers is shown as mounted on an arm 288 which is pivoted bymeans of a screw 289. and is held by a spring 290 in contact with the.film 3. Stop 29! may be used to limit the" movement of these arms. Theadjustment of the spring tension'should be such that the rollers l2 areadapted to take up the shock when the film is reversed and preventtearing of the film.

It is to be noted in this connection that when the film is reversed oneof the reels 2 will be full and correspondingly heavy and will berotating in a direction to wind up thefilm thereon. When the film, issuddenly reversed by reversal ;of the sprockets l0the inertia of thisfull reel must be overcome and the reel started to rotate in theopposite direction against the drag exerted by the take-up mechanism.Thev pressure of the springs 290 is adjusted so as to accomplish this,the arms 288 swinging inwardly as'the film tightens, and these arms arereturned by the springs .290 whenreversal occurs in the direction of thereel for taking up. It is to. be understood that suitable adjustment maybe provided for varying the pressure of the springs 290 if desired.

Idler rollers M are mounted in theusual manner to hold the film incontact with the drive sprockets l0. Idler rollers l3 are mountedbetween the feed sprockets l0 and the film gate in which these'idlerrollers are attached to hold the film in contact with the feed sprocketsand. also to maintain the film in engagement with a predetermined sectorof the aperture plate as shown more in detail in Fig. 13. In Fig. 13idler rollers iii are shown mounted so that they may be adjusted tocompensate for variations in length of the film due to temperaturechanges, etc., the mounting being arranged so that this adjustment canbe effected without changing the arc of contact of the fihn with thefilm gate. This latter feature is of importance inasmuch as the re-.versal of the film is automatically effected when the conducting strip1 thereon engages the film gate; consequently any variation in the arcof contact would alter the timing of the control mechanism. In theembodiment shown this adjustment is obtained by mounting each idlerroller l3 upon a shaft 2295 (Figs. 13 and 15) which is held in anelongated'slot 293 in a plate 29 attached to the panel l8 in'the case ofthe recording head, or to the panel 205 in the case of the reproducinghead. A bushing 298 is disposed about the shaft 295 and is adapted to beclamped against the plate 291 by means of a thumb screw 299. The rolleri3 is mounted for free rotation on this bushing 298.

The slot 205 is elongated in a direction parallel to the line of feed ofthe film toward the film gate, that is, in a direction parallel to atangent to the film gate at the point where the conducting strip 1 onthe film comes into contact with the film gate as shown in Fig. 13.Consequently adjustment of the idler roller l3 along this slot 296 doesnot change the angle of the feed of the film past the sound gate anddoes not change the timing of the control mechanism. It is to beunderstood, of course, that other suitable adjusting means may be usedif desired in place of that shown and described above.

Film drive of Fig. 17

Fig. 1'7 shows a-modified form of film drive which may be used in placeofthe two feed sprockets l0. In this embodiment the film gate H isconstructed in the manner described above.

In place of the two feed sprockets l0, however, there is provided asingle feed sprocket 305 which is of sufficient diameter so that thefilm may contact over two separate portions of the surface thereof. Thissprocket 305 is driven by gear 306 which meshes with the gears as' shownin Fig. 1'7. The film 3 passes in drivingengagement with a portion ofthe surface of the feed sprocket 305 with which it is held in contact byadjustable rollers 301. Thence the film passes around the film gate IIand in driving engagement with another portion of the sprocket 305 withwhich it is held in contact by adjustable rollers 308. The rollers 301and 308 are mounted so that they can be displaced to permit the film tobe threaded over the sprocket 305'. In

above.

Control circuit The control for reversing the drive and for stepping theaperture plate from one sound track to the next is shown in Fig. l9.This circuit shows an A. C. supply line 310 driving the motor 20 andfeeding the primary of the transformer 311 through a switch 312 by whichthe entire system may be disconnected as desired. The secondary 313 oftransformer 311 is connected across the anode and cathode of a spacedischarge tube 314 of standard construction such as a grid glow tube. Arelay 315 is connected in series with one of the leads from thesecondary 313 to the tube 314 in such a way that the space current ofthe tube passes through relay 315 and energizes the same. The tube 314is' provided with a grid 311 which is adjustably connected to thecathode of the tube through an impedance.

such as a variable condenser 321. The biasing potential on the grid 311may be adjusted by condenser 321 to a value sufliciently negative toblock the tube. When the capacityhereinafter described is added to thegrid circuit, however, thepotential ofthe grid is altered sufilcientlyto permit passage ofspace current through the Y normally blocked anddoes not pass current. The

tube. For this purpose the grid 311 is connected to an insulated ring149 of the recording head or the insulated ring 253 of the reproducinghead by means of the respective contact brushes 110 and 234.

The bottom ring 148 of the recording head or the bottom ring 252 of thereproducing head is grounded to the unit. Consequently when the metallicstrip i of the film engages these rings the effect is to add capacity tothe grid circuit thereby changing the grid biasing potential andpermitting space current to flow. This space current energizes relay 315which there upon attracts its armature and closes its contact 325,completing the circuit from one side of the supply line 3111 through animpulse relay 321 and back to the other side of the supply line. Therelay 321 is thus connected across the line and is energized thereby.The relay 321 is of the impulse type which is adapted to move itsarmature 328 alternately to close contact 329 or 333 at successiveactuations of the relay.

A switch such as a push button 321] may be connected in parallel to thecontact points 325 of relay 315 by which the electrical circuit may bemanually operated to actuate the relays. when desired. The contacts 329and 330 are connected respectively to blades 332 and 331 of atriple-pole triple-throw switch 333. The arms.-

ture 323 is connected by a line 334 to one side of the supply line.Contacts 335 and 336 of switch 333, which cooperate with the blade 331,are-connected together and to one of the solenoids 33 as well as to asuitable rectifier such as a rectox unit 331 which is connected to aholding electromagnet 1011. In the embodiment of the supply line. Theleft hand contact 3 for the blade 332 is connected to both a rectoxunit363 which supplies the holding electromag: net 1111! on the leftside of the arm 92, as 'well as to the left hand solenoid 39 and thencethrough lead 341 to a lower contact 342 which is adapted to be engagedby the arm 338 when the arm 92 has been depressed by actuation of theright hand solenoid. when starting the machine the arm 92 is in aneutral position due to the balancing springs 133, which allows theclutches to remain in neutral position. The motor 23 is then started andallowed to come up to speed. Thereafter the switch 312 is closed toenergize the control circuit.

The switch 312 has a make, break, and then make circuit whereby in theevent'that the arm 323 of impulse relay 321 is not closing contact 3311an impulse will be transmitted through contact arm 355 and impulse relay321 causing arm 328 to close contact 330 for starting purposes. Thissafety factor insures that arm 328 will always be in the correctposition for moving the film in the one direction at starting time. Thearm 328 is now making contact with contact 333 as shown in Fig. 19. Thegrid glow tube 314 is relay 315 is, therefore, deenergized and is onlyenergized when the conducting strip 1 of the film makes contact with theabove-mentioned rings of the film gate, whereupon the potential on grid311 of tube'314 is altered thereby allowing space current to pass. Thisspace current passing through relay 315 energizes the same and causesthe relay to close contact 325 thereby completing the circuit throughand energizing the impulse relay 321 'to shift the arm 328, therebyopening contact 331) and closing contact 329.

The contact 329 supplies current through blade 332 and contact 340 ofswitch 333 to the rectox unit 363, which I shall refer to as a holdingcurrent, and also to the left-hand solenoid 9B, the

circuit to which is completed through contact 342 and arm 338.Energizaticn of the left-hand solenoid 95 pulls the left end of arm 92downward, thereby reversing the drive of the machine in the mannerdescribed in connection with Figs. 3 to 5 and at the same time openingcontact 332 and closing contact 331. The left-hand solenoid 93 isaccordingly energized only momentarily and is deenergized as soon as ithas been actuated to shift the arm 92. However, holding current suppliedthrough rectox'unit 363 is supplied to the associated electromagnet M11as shown in Fig. 19.

- The film is now running in the reverse direction, and, when it hasagain reached the end of its travel so that the opposite conductingstrip '1 contacts with the above-mentioned rings on the film gate, acircuit is again completed which to the right-hand solenoid 99, contact331 now shown these contacts are connected to the right hand solenoid39. The circuit of this solenoid is completed through a contact 331engaging an arm 333 carried on the arm 32. The arm 333 is connected by alead 339 to the opposite side 76 being closed. This energization of therighthand solenoid 33 again actuates arm 92, reversing the positionthereof and reversing the direction of drive in the manner describedabove. It will be noted, therefore, that each successive engagement ofthe conducting strips 1 with the rings or the film gate causes reversalof the drive. In order to actuate the ratchet mechanism in synchronismwith the reversal of drive, the solenoid .2l2 of Fig. 11 is connected toone side of the supsolenoid M2 and causes the ratchet mechanism to stepthe aperture plate to its next position. The shifting of the apertureplate on the reversal of drive is accordingly accurately synchronized sothat, in recording, the successive sound tracks .are joined by uniformloops as shown in Fig. 18,

and, in reproducing, the scanning ray follows the path of these loops asit is shifted from .one sound track to the next. In this way any breakin the sound is avoided. The reversing and shifting of the apertureplate takes place so rapidly that not more than one cycle of soundenergy is lost and this is not suflicient to produce any audi-' bleeffect in the reproduced sound.

In some instances the sound tracks, instead of being continuous asdescribed above, may be ,arranged so that a plurality of selections orprograms are incorporated on the same film.- A diflerent'selection may,for example, be recorded on each sound track. In this event the tracksmay all be recorded in the same direction and when the selection hasbeen completely played it is necessary to stop the machine and rewindthe film prior to the playing of the next selection. By means of theconnections shown in 19 the film may be stopped for the above purpose byshifting the triple-pole switch 333 so that blades 33I and 332 engagethe second contacts. The second contact 339,is not connected to anyelectric circuit. .Therefore, when arm 328 engages contact 329 noelectrical circuit is made through blade 332, hence rocker arm 92 ismoved to a neutral position by means of springs E35 causing the clutchmechanisms to disengage and bringing the film to a dead stop. However,in the event" the record referred to above is a short record and manualoperation is desired to stop this. record from running to the end of thefilm, push. button 32% may be used to energize impulse relay 82? so thatthe above-mentioned circuit is opened. It is to be noted that contact3311 is closed while the arm '32 is in neutral position and when the:right end of arm 32 is in elevated position. The machine can thus bealternately started and stopped by button 32d.

In order to actuate the high speed rewind,-

the rewind solenoid M is connected from one side of the line to lead 339through a switch 3M to a third contact 352 adapted to engage the blade332 of switch 333. After the machine has been stopped in the mannerdescribed above, switch 338 is shifted to a third position to closecontact 332 thereby completing the circuit from contact 329 throughblade 332, contact 332 and in I the switch 858, to the solenoid I25,thus ca rewind mechanism shown in Fig. 14 to e eecloses contact 339thereby energizing the right hand solenoid 99 and causing the machine toagain operate. The machine will then operate until another impulsecloses contact. 329 of impulse relay 321 which then opens the electricalcircuit through blade 332, allowing arm 92 to again be neutralized bysprings I39.

Summarizing the above, it is noted that with switch 333 in the positionshown in Fig. 19 the machine is automatically reversed at each end ofthe sound track by contact strip I and is adapted to continuously playthe entire sound track. With switch 333 in the second position. themachine is alternately operated in one direction by energization of theright-handsolenoid 99 when contact 3391s closed, or is stopped bydeenergizing the circuit when contact 329 is closed allowingneutralizing springs I39 to neutralize rocker arm 92. With switch 333 inthe third position the high speed rewind mechanism is operated whencontact 329 is closed to complete a circuit through solenoid I25 and themachine is stopped when contact 330 is closed to deenergize the circuitallowing springs I30 to again neutralize rocker arm -92.

It is evident, therefore, that any desired combination of manual andautomatic control can be Operation The operation of the various-elementshas been described above. It is to be noted that the machine as a wholeis intended to operate with a multiple track. film for continuouslyplaying the entire sound record or for selectively playing certainindividual sound record tracks. The machine is adapted to be used eitherfor recording or reproducing bythe simple expedient of providingseparate and interchangeable recording and reproducing heads, both ofwhich are mounted as a unit and may be removed from the machine with aminimum amount of labor and time. The film is fed from one reel, overthe drive sprockets and film gate and onto the opposite reel. The drivesprockets it] are actuated in unison by the driving mechanism shown inFigs. 2 to 5, the direction of drive being contuated for rewinding thefilm. The switch dell is associated with an arm 853 whichis carried byarm 92 and is adapted to open the circuit whenever arm at is out ofneutral position, thereby preventing accidental operation'of the rewkidmechanism when either of thevclutches; is enga ed.

In order to automatically stop the machine ,when the film has beenrewound, the conducting strip I actuates the relay mechanism asdescribed above, thereby opening the electrical circuit so that nocurrent can pass to any solenoid,

trolled by the position of arm 92 which actuates the clutches $8. Witharm 32 in neutral position the machine is stopped. With arm 92 tiltedeither upwardly or downwardly the film is fed in a direction dependentupon the particular clutch which is engaged thereby.

It is to be noted that the light source; telescope tube and associatedparts are stationary,

- Figs. '6. 8, 11 and 12 so as to shift the scanning ray from one soundtrack to another at each actuation thereon. This'ratchet mechanism iscontrolled by a solenoid which is connected in and allowing thebalancing springs I33 to bring is parallel to the solenoid'controllingthe reversal of feed, consequently exact synchronism is assured.

- While the film gate is shown as having rotating rings it is obviousthat stationary rings could be used if desired, in which case one of therings would be insulated from the machine and the other grounded theretoso that a circuit would be completed by contact strips, 1 for actuatingthe control mechanism whenever these strips engage the appropriate partof the sound gate. It is also evident that the sound gate may be ofother construction and shape A round gate-has been shown for convenienceinasmuch as it, is

adapted to receive the photoelectric cell and also to serve as a guidefor the film. In some instances it'may be desirable to omit part of thehousing in which case the photoelectric cell can be mounted in back ofthe film gate. The de tails of construction and mounting of thetelescope tube and the lens system may also be varied as desired. InFig. 6 a particular mechanical .connection has been shown .forpermitting the aperture plate to be shifted with the telescope tubewhile maintaining driving engagement with gear i 90, but it is evidentthat any other suitable driving connection which permits of thisrelative adjustment may be employed.

Although certain details of construction and combination of parts havebeen specifically shown and described for purposes of illustrating theinvention it is to be understood that various changes and modificationsmay be made therein as will be apparent to a person skilled in the art.

each of said second disks alternately driving its film reel in taking upthe film while the opposite friction takeup slips allowing the film tobe pulled from its reel, idler rollers mounted between each feedsprocket andthe film gate, and means for adjusting said idler rollers tocompensate for variation in shrinkage of film between the feed sprocketsallowing a predetermined tension to be applied to the sound gate at apredetermined arc of contact between said film and said film gateregardless of the adjusted position of said idler. v

3. In a photographic sound record apparatus for recording on orreproducing from a film having a plurality of spaced parallel soundtracks thereon, a film gate, means to support a pair of film reels, feedsprockets mounted on opposite sides of said film gate, means for passingsaid film between said reels over said film gate and in The invention istherefore to be limited only in accordance with the following claims.

The invention claimed is:

1. In a photographic sound record apparatus for recording on orreproducing from a film having a plurality of spaced parallel soundtracks thereon, a film gate, means to support a pair of film reels, feedsprockets mounted on opposite sides of said film gate, means for passingthe film between said reels over said film gate and in drivingengagement with both of said sprockets, reversible means for drivingboth of said sprockets in unison, a friction takeup mechanism drivingsaid reels, said mechanism comprising a pair of friction disks, a drivecontinuously driving said disks in opposite directions, separate shaftscarrying said film reels, a second friction disk fixed to each of saidshafts and engaging the respective first-mentioned disks, each of saidsecond disks alternately driving its film reel in taking up the filmwhile the opposite friction takeup slips allowing the film to be pulledfrom its reel, and spring pressed idler rollers engaging the film asitpasses to or from each to maintain a predetermined tension on saidfilm and to take the shock from the film when the drive is reversed.

2. In a photographic sound record apparatus for recording on orreproducing from a film having a plurality of spaced parallel soundtracks thereon, a film gate, means to support a pair of film reels, feedsprockets mounted on opposite sides of said film gate, means for passingsaid film between said reels over said film gate and in drivingengagement with both of said sprockets, reversible means for drivingboth of said sprockets in unison, a friction takeup mechanism drivingsaid reels, said mechanism comprising a pair of friction disks, a drivecontinuously driving said disks in opposite directions,

- separate shafts carrying said film reels, a second friction disk fixedto each of said shafts and engaging the respective first-mentioneddisks,

of said reels driving engagement with both of said sprockets, reversiblemeans for driving both of said sprockets in unison, a friction take-upmechanism driving said reels, said mechanism comprising a pair offriction disks, a drive continuously driving said disks in oppositedirections, separate shafts carrying said film reels, a secondfrictiondisk fixed to each of said shafts and engaging the respectivefirst-mentioned disk, each of said second disks alternately driving itsfilm reel in taking up the film while the opposite friction take-upslips allowing the film to be pulled from its reel, idler rollersmounted between each of said sprockets and said film'gate, and means toadjust said idler rollers parallel to the path of the film to compensatefor variations in thefilm while maintaining a predetermined arc ofcontact between said film and said film gate.

4. In a photographic sound record apparatus for recording on orreproducing from a film having a plurality of spaced parallel soundtracks thereon, a film-gate, means to support a pair of film reelsbetween which the film is passed over said film gate, a pair of frictiontake-up mechanisms driving said reels, means to adjust the friction ofboth of said take-up mechanisms so as to supply a force proportional tothe weight of film to be driven, and an adjusting knob to control saidadjusting means of both said take-up mechanisms at the same time,- saidknob being graduated to designate the length of film with. which theparticular adjustment is adapted to operate.

5. In a photographic sound record apparatus for recording on orreproducing from a film having a plurality of spaced parallel soundtracks thereon, a film gate, means to support a pair of film reelsbetween which the film is passed over said film gate, a friction take-upmechanism driving said reels, said mechanism comprising a pair offriction disks, a motor constantly driving both said disks in oppositedirections, a pair of shafts each carrying one of said reels, a secondpair of friction disks each keyed to one of said shafts and engaging oneof the said first-mentioned disks, spring means for controlling thedriving friction of said disks, a pair of pivoted arms to control thetension of said spring means, a member pivotally engaging both of saidarms to control the position thereof, and adjusting means for causingaxial movement of said memher to thereby controlthe driving forceexerted by said friction disks.

LEONARD A. HERZIG.

